drm/i915: Refactor translate_signal_level()

Convert the big switch statement in translate_signal_level() into a neat
table. The table also serves as documentation for the translation
tables. We'll also have other uses for this table later on.

v2: Remove superfluous space (David)

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170223173507.17600-2-ville.syrjala@linux.intel.com
Reviewed-by: David Weinehall <david.weinehall@linux.intel.com>
This commit is contained in:
Ville Syrjälä 2017-02-23 19:35:06 +02:00
parent 7d1c42e679
commit 97eeb87276
1 changed files with 21 additions and 39 deletions

View File

@ -34,6 +34,19 @@ struct ddi_buf_trans {
u8 i_boost; /* SKL: I_boost; valid: 0x0, 0x1, 0x3, 0x7 */
};
static const u8 index_to_dp_signal_levels[] = {
[0] = DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_0,
[1] = DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_1,
[2] = DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_2,
[3] = DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_3,
[4] = DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_0,
[5] = DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_1,
[6] = DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_2,
[7] = DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_0,
[8] = DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_1,
[9] = DP_TRAIN_VOLTAGE_SWING_LEVEL_3 | DP_TRAIN_PRE_EMPH_LEVEL_0,
};
/* HDMI/DVI modes ignore everything but the last 2 items. So we share
* them for both DP and FDI transports, allowing those ports to
* automatically adapt to HDMI connections as well
@ -1604,48 +1617,17 @@ static void bxt_ddi_vswing_sequence(struct drm_i915_private *dev_priv,
static uint32_t translate_signal_level(int signal_levels)
{
uint32_t level;
int i;
switch (signal_levels) {
default:
DRM_DEBUG_KMS("Unsupported voltage swing/pre-emphasis level: 0x%x\n",
signal_levels);
case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_0:
level = 0;
break;
case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_1:
level = 1;
break;
case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_2:
level = 2;
break;
case DP_TRAIN_VOLTAGE_SWING_LEVEL_0 | DP_TRAIN_PRE_EMPH_LEVEL_3:
level = 3;
break;
case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_0:
level = 4;
break;
case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_1:
level = 5;
break;
case DP_TRAIN_VOLTAGE_SWING_LEVEL_1 | DP_TRAIN_PRE_EMPH_LEVEL_2:
level = 6;
break;
case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_0:
level = 7;
break;
case DP_TRAIN_VOLTAGE_SWING_LEVEL_2 | DP_TRAIN_PRE_EMPH_LEVEL_1:
level = 8;
break;
case DP_TRAIN_VOLTAGE_SWING_LEVEL_3 | DP_TRAIN_PRE_EMPH_LEVEL_0:
level = 9;
break;
for (i = 0; i < ARRAY_SIZE(index_to_dp_signal_levels); i++) {
if (index_to_dp_signal_levels[i] == signal_levels)
return i;
}
return level;
WARN(1, "Unsupported voltage swing/pre-emphasis level: 0x%x\n",
signal_levels);
return 0;
}
uint32_t ddi_signal_levels(struct intel_dp *intel_dp)